2,131 research outputs found

    Subregional Population Projections for Tuscany

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    The natural growth of the Tuscany region of Italy has been relatively stable since 1951 (with the natural growth rate equal to zero). This paper is one of the first contributions to the population analysis of this region. With the help of models developed at IIASA (Willekens and Rogers 1978), an attempt is made to answer questions such as: How many people will live in Tuscany in the next 10, 15, 20 years if migration flows remain constant? Will the present migration pattern persist? What effects have changes in international migration had on the population of Tuscany over the last ten years? What are the rates of change and the share of population in the subregions of Tuscany

    Light emitting diodes technology in public light system of the municipality of Rome: an economic and financial analysis

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    This study evaluates an investment project concerning the redevelopment of the public lighting of the Municipality of Rome. In particular, we consider the replacing of the traditional lamps of the system with light emitting diodes lamps. We consider the factors that affect this kind of project: The cost of energy, the manteinance cost, the investment cost and the weighted average cost of capital. Our results underline the reduction of energy consumption and of the maintenance costs, lower emissions of CO2 into the atmosphere, the reduction of light pollution, the positive effects on road safety and the indipendence by incentives

    Shari'ah-compliant finance: a possible novel paradigm for green economy investments in Italy

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    In Italy, the dramatic reduction of government incentives has caused a decrease of investments in the renewable energy sector. For this reason, it is necessary to rethink funding techniques, extending the analysis to different cultural and financial models. In this paper, we study the incentive-dependency of an Italian case study in the wind energy sector in order to reach grid parity, comparing the obtained results with those of Islamic finance and conventional finance. In particular, we propose that Sukuk Islamic finance instruments be used for the realization of real assets in Shari'ah-compliant finance that prohibits interest rates, as in conventional financial markets, and we present the building cost thresholds necessary to achieve grid parity. Our results highlight the importance of incentives and the applicability of the use of Sukuk instruments for sustainable investments in the wind energy sector, which is crucial in the framework of current efforts against climate change as well as efforts to reduce greenhouse gas emissions

    Hydrogen Arrangements on Defective Quasi-Molecular BN Fragments

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    Considering the ever-increasing interest in metal-free materials, some potential chemical applications of quasi-molecular boron nitride (BN) derivatives were tested. Specifically, the behavior of BN fragments was analyzed when given defects, producing local electron density changes, were introduced by using topological engineering approaches. The inserted structural faults were Schottky-like divacancy (BN-d) defects, assembled in the fragment frame by the subtraction of one pair of B and N atoms or Stone-Wales (SW) defects. This study is aimed at highlighting the role of these important classes of defects in BN materials hypothesizing their future use in H-2-based processes, related to either (i) H-2 activation or (ii) H-2 production, from preadsorbed hydrogenated molecular species on BN sites. Here, it has been observed that BN species, embodying SW defects, are characterized by endothermic H-2 adsorption and fragmentation phenomena in order to guess their potential use in processes based on the transformation or production of hydrogen. On the contrary, in the presence of BN-d defects, and for reasons strictly related to local structural changes occurring along with the hydrogen rearrangements on the defective BN fragments, a possible use can be inferred. Precautions must be however taken to decrease the material rigidity that could actually decrease the ability of the BN fragment to flatten. This conversely seems to be a necessary requirement to have strong exothermic effects, following the rearrangements of the H-2 molecules

    Introduction to the study of the bryological flora of the Batumi Botanical Garden (Georgia).

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    A preliminary list of 22 bryophytes growing in the Batumi Botanical garden is provided. From chorological point of view, temperate and boreo-temperate taxa prevail while with regard to ecological behaviour, mesophilous taxa are the most numerous and with respect to light requirements equivalently sciaphilous and eliophilous taxa are represented. The mosses Fissidens dubius and Cyrtomnium hymenophylloides are recorded for the first time in Georgia

    Efficient solar cells by space processing

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    Thin films of electron beam evaporated silicon were deposited on molybdenum, tantalum, tungsten and molybdenum disilicide under ultrahigh vacuum conditions. Mass spectra from a quadrapole residual gas analyzer were used to determine the partial pressure of 13 residual gases during each processing step. Surface contamination and interdiffusion were monitored by in situ Auger electron spectrometry. The presence of phosphorus in the silicon was responsible for attaining elevated temperatures with silicide formations. Heteroepitaxial silicon growth was sensitive to the presence of oxygen during deposition, the rate and length of deposition as well as the substrate orientation

    Interstellar catalysts and the PAH universe

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    Organic molecules in interstellar space are important as they influence the structure of galaxies and star formations. Studying catalytic processes in space allows us to understand how molecular species are formed and chemically evolved in the interstellar medium and solar system objects. Quantum chemical methods, such as “Density Functional Theory” (DFT), can be employed to study the chemical pathways for the formation of molecular species, which is challenging with only observations and experiments. This thesis studies, with DFT methods, how polycyclic aromatic hydrocarbons (PAHs), the most abundant organic species in space, catalyze the formation of molecular hydrogen in the interstellar medium. Specifically, how linear PAHs become superhydrogenated and how the presence of Stone Wales defect in PAHs contributes to their catalytic activity for molecular hydrogen formation. In addition, this thesis reports the study of the catalytic activity of forsterite, a silicate mineral abundant in grains, asteroids, and meteorites. Specifically, the presence of Schottky MgO vacancy in forsterite can catalyze the C-H activation of PAHs as the first step to study the breakdown reaction of PAHs in asteroidal settings. The latter is indispensable to understand the formation of the so-called organic inventory of solar system objects.Horizon 2020 Marie Skłodowska-Curie ITN EUROPAH (grant number 722346); Spinoza award by the Dutch Research Council (NWO)Sterrewacht - OU

    Human brain distinctiveness based on EEG spectral coherence connectivity

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    The use of EEG biometrics, for the purpose of automatic people recognition, has received increasing attention in the recent years. Most of current analysis rely on the extraction of features characterizing the activity of single brain regions, like power-spectrum estimates, thus neglecting possible temporal dependencies between the generated EEG signals. However, important physiological information can be extracted from the way different brain regions are functionally coupled. In this study, we propose a novel approach that fuses spectral coherencebased connectivity between different brain regions as a possibly viable biometric feature. The proposed approach is tested on a large dataset of subjects (N=108) during eyes-closed (EC) and eyes-open (EO) resting state conditions. The obtained recognition performances show that using brain connectivity leads to higher distinctiveness with respect to power-spectrum measurements, in both the experimental conditions. Notably, a 100% recognition accuracy is obtained in EC and EO when integrating functional connectivity between regions in the frontal lobe, while a lower 97.41% is obtained in EC (96.26% in EO) when fusing power spectrum information from centro-parietal regions. Taken together, these results suggest that functional connectivity patterns represent effective features for improving EEG-based biometric systems.Comment: Key words: EEG, Resting state, Biometrics, Spectral coherence, Match score fusio

    Oral amelanotic melanoma: a case report

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    Objectives. Primary oral melanoma is a very rare malignancy, representing about 0.5% of all melanomas, characterized by a wide clinical-histological variability and a very aggressive behavior. Aim of the present study is to describe a case of oral amelanotic melanoma, an infrequent variant with a poorer prognosis than that of pigmented melanomas for a more aggressive biological behavior and frequent delays for the correct diagnosis and for starting the treatment. Case report. A 53-year-old white man referred at the Department Surgical, Oncological and Oral Sciences for a macular, scarsely pigmented lesion with irregular margins, located on anterior region of hard palate. The lesion, completely asymptomatic and without any history of trauma or injury, was observed by his dentist some months ago. The patient was a smoker (about 20 cigarettes a day for 30 years) and his anamnesis was negative for any systemic diseases and drug assumption. Histological examination, following the incisional biopsy, showed the hyperplasia of the junctional melanocytes with occasionally dendritic appearance and light atypia; on the recommendation of pathologist, a second incisional biopsy was performed, and a definitive diagnosis of “amelanotic melanoma in situ” was confirmed. After diagnosis, the patient was referred to the unit of Head and Neck Surgery for staging and surgical approach of the lesion. Conclusions. This case report underlines the importance to perform biopsy of all lesions of the oral cavity to rule out malignancy, even when slightly colored, asymptomatic and with a clinically harmless presentation. Besides benign diseases (e.g melanotic macules, nevi, extravasation of blood pigments, amalgam tattoos and deposition of other exogenous/endogenous pigments), rare variant of non-pigmented melanoma should be considered in order to avoid a dangerous diagnostic and therapeutic delay
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